Compressor intake system

ABSTRACT

A compressor intake system including an end cap having an interior surface, an exterior surface, a perimeter rim, a groove proximate the perimeter rim, and a substantially centrally disposed extended portion including a plurality of air inlet passages, an O-ring configured to be circumferentially disposed proximate the interior surface of the end cap at the groove, a filter including a first end configured to be disposed adjacent the air inlet passages and the interior surface of the end cap and a second end, and a retainer including a plurality of openings wherein the retainer is configured to be disposed proximate the second end of the filter so as to retain the filter proximate the air inlet passages and the openings.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of co-pending U.S. provisional patent application Ser. No. 61/355,672, filed Jun. 17, 2010, which application is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

This invention relates to a compressor intake system and, more particularly, to a compressor intake system for use in a compact oxygen concentrator.

BACKGROUND OF THE INVENTION

Conventional oxygen concentrators generally include a compressor for receiving ambient air to be fractionated, such as by a pressure swing absorption method, in order to supply an output stream which has a high concentration of oxygen for medical or other purposes where an oxygen rich gas is required. While oxygen concentrators have proven to be very useful for many medical and other applications, noise level, at least partially due to the compressor intake system, can limit their usefulness in many environments, such as public locations or at health treatment facilities. Accordingly, a highly efficient compact compressor with reduced operating noise is desired in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is disclosed with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view of a compressor including the intake system according to some preferred embodiments of the present invention;

FIG. 2 is an exploded view of a compressor intake system according to some preferred embodiments of the present invention;

FIG. 3 is a cross-sectional view of a compressor intake system according to some preferred embodiments of the present invention;

FIG. 4 is a perspective rear view of the end cap of a compressor intake system according to some preferred embodiments of the present invention;

FIG. 5 is a perspective rear view of an end cap and an O-ring according to some preferred embodiments of the compressor intake system;

FIG. 6 is a perspective rear view of an end cap, an O-ring and a filter of according to some preferred embodiments of the compressor intake system; and

FIG. 7 is a perspective rear view of the an end cap, an O-ring, a filter and a retainer according to some preferred embodiments of the compressor intake system.

Corresponding reference characters indicate corresponding parts throughout the several views. The examples set out herein illustrate some preferred embodiments of the invention but should not be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION

Referring to FIG. 1, there is shown an exemplary compressor 1 including the intake system 2 according to some preferred embodiments of the present invention. The compressor 1 includes at least one housing 4 preferably made of a rigid, heat-conducting material such as aluminum, and a motor (not shown) disposed adjacent the housing 4. The motor can be a standard electric motor and preferably includes a drive shaft with two opposing ends. The compressor 1 further includes a compressor head at each end (as shown) including a piston assembly (not shown) disposed in a cylinder 3 and configured to engage a drive shaft (not shown). In operation, the motor rotates the drive shaft which converts the rotational motion into linear motion at the interface with each piston. As ambient air is drawn into the compressor 1 by vacuum pressure through the intake system 2, described in detail below, it moves by pressure differential through a valve (not shown), such as a butterfly valve, in the piston and, in the case of an oxygen concentrator, is communicated to one or more adsorber beds to be fractionated.

Referring to FIGS. 1-2, some preferred embodiments of the compressor intake system 2 include an end cap 12 having an interior surface, configured to be disposed toward the housing 4 when attached, and an exterior surface, an O-ring 14, a filter 16, and a retainer 6 as well as fastening means, such as one or more screws 18, 20 for fastening the retainer 6 to the end cap 12 and the end cap 12 to the housing 4, respectively. Ambient air is received through the end cap 12, and specifically through a plurality of air inlet passages 10 preferably located in an extended and centrally disposed portion 7 of the end cap 12. The extended portion 7 preferably does not extend beyond the plane of the exterior surface of the end cap perimeter rim 5. In one exemplary embodiment, the air inlet passages 10 extend radially at regular angle intervals such as at the 45 degree intervals shown in FIGS. 1-2 and 4-5 and do not overlap or converge.

Optionally, one or more spoke portions 11 also extend radially at substantially the same regular angle intervals as the air inlet passages 10 from the extended portion 7 toward the perimeter rim 5 of the end cap 12. One or more optional recessed portions 9 may be disposed between one or more spoke portions 11 as shown in FIG. 1. Also optionally, the plurality of spoke portions 11 may not extend to the perimeter rim 5 but, instead, extend to a recessed portion 13 disposed between the extended portion 7 and the perimeter rim 5 of the end cap 12.

Referring to FIGS. 2-7, a filter 16 of the compressor intake system, preferably made of synthetic or felt material, is configured to be disposed adjacent the air inlet passages 10 and the interior surface of the end cap 12. Preferably, the filter 16 does not extend beyond the plane of the furthest interior portion of the interior surface of the end cap 12. In one exemplary preferred embodiment, a retainer 6 is configured to be disposed preferably substantially flush with the interior surface of the end cap 12 so as to retain the filter 16 in position. The retainer 6 may be attached to the end cap 12 by one or more screws 20 or other fastening means. The retainer includes a plurality of concentric openings 8 through which the filtered ambient air is drawn. Both the retainer 6 and the end cap 12 may be made of a hard, rigid material and may be plastic molded, for example.

An O-ring 14, preferably a standard O-ring made of silicone or other compressible elastomeric material, is configured to be disposed adjacent the interior surface of the perimeter rim 5 of the end cap 12 in an O-ring groove 15 which is circumferentially disposed and configured to receive an O-ring 14. The O-ring is further configured to conform to a shape having substantially similar circumference as the housing 4 at the interface 19 between the end cap 12 and the housing 4. Upon attachment of the end cap 12 to the housing 4, the O-ring 14 provides a seal to keep air, dirt, liquids, and other debris from entering the housing 4 at the interface 19. The end cap 12 may be press fit, adhesive fit, and/or fastened to the housing such as by one or more screws 18 at one or more threaded bores 17 disposed in the housing 4, for example.

In one exemplary preferred embodiment, the O-ring groove 15 has sufficient depth to allow a lip portion 23 of the end cap 12 to extend beyond the interface 19 and adjacent the side wall 21 of the housing 4 when attached. The end cap 12 further includes one or more apertures 25 for receiving fasteners 18 for attachment to the housing 4 as well as one or more threaded bores 24 for attachment of the retainer 6. A portion of the end cap 12 preferably disposed toward the center is configured to receive the filter 16 such that at least a portion of the filter is disposed adjacent each air passage inlet 10 as well as each concentric opening 8.

While other arrangements are contemplated, we have found the arrangement of components in the preferred embodiments shown to significantly reduce decibel level output of the compressor 1 and therefore the overall noise output of an oxygen concentrator apparatus. Specifically, the configuration of air inlet passages 10 shown in the preferred embodiment provides for reduced pressure incident the end cap 12 as well as an overall reduction in sound level. Similarly, the configuration of concentric openings 8 shown in the preferred embodiments results in reduced operating sound level while also providing sufficient air flow volume.

It should be noted that means of assembly of the compressor parts as described is by way of example only. While other configurations are possible, the configuration of spoke portions 11 and recessed portions 9, 13 shown in the preferred embodiments provide for increased strength and structural support particularly upon bolting, or other attachment, of the end cap 12 to the housing 4. Alternatives to the means of mechanical assembly may be employed, such as adhesives and brazing.

While the principles of the invention have been described herein, it is to be understood by those skilled in the art that this description is made only by way of example and not as a limitation as to the scope of the invention. For example, it should be noted that the present invention may be applied to a dual head or single head compressor. Other embodiments are also contemplated within the scope of the present invention in addition to the exemplary embodiments shown and described herein. Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention. 

1. A compressor intake system, comprising: an end cap having an interior surface, an exterior surface, a perimeter rim, a groove proximate the perimeter rim, and a substantially centrally disposed extended portion including a plurality of air inlet passages; an O-ring configured to be circumferentially disposed proximate the interior surface of the end cap at the groove; a filter including a first end configured to be disposed adjacent the air inlet passages and the interior surface of the end cap and a second end; and a retainer including a plurality of openings wherein the retainer is configured to be disposed proximate the second end of the filter so as to retain the filter proximate the air inlet passages and the openings.
 2. The compressor intake system of claim 1 further including first fastening means for fastening the retainer to the end cap and second fastening means for attaching the end cap to a compressor housing.
 3. The compressor intake system of claim 1 wherein the extended portion does not extend beyond the plane of the exterior surface of the end cap perimeter rim.
 4. The compressor intake system of claim 1 wherein the plurality of air inlet passages extend radially at regular angle intervals with respect to the center of the extended portion.
 5. The compressor intake system of claim 4 wherein the plurality of air inlet passages includes eight air inlet passages extending radially at 45 degree angle intervals.
 6. The compressor intake system of claim 4 wherein the air inlet passages do not overlap or converge.
 7. The compressor intake system of claim 4 wherein the end cap further includes: a plurality of spoke portions extending radially at substantially similar regular angle intervals as the air inlet passages from the extended portion toward the perimeter rim of the end cap; and at least one recessed portion disposed between at least two spoke portions.
 8. The compressor intake system of claim 1 wherein the filter does not extend beyond the plane of the furthest interior portion of the interior surface of the end cap.
 9. The compressor intake system of claim 1 wherein the plurality of openings are substantially concentric and disposed substantially radially with respect to the center of the retainer.
 10. The compressor intake system of claim 1 wherein the extended portion has an inner diameter, the retainer has a diameter and the filter has a diameter, and wherein the retainer diameter is greater than the extended portion inner diameter and the filter diameter is less than the extended portion inner diameter.
 11. The compressor intake system of claim 10 wherein the retainer is configured to be disposed substantially flush with the interior surface of the end cap and means for fastening the retainer to the end cap including at least one aperture in the retainer, at least one threaded bore disposed proximate the interior surface of the end cap, and at least one threaded fastener for extending through the retainer aperture and threading to the threaded bore.
 12. A compressor, comprising: a housing including a head wherein the head includes a circumferentially disposed interface; an end cap having an interior surface, an exterior surface, a perimeter rim, a groove proximate the perimeter rim wherein the groove has a substantially similar circumference as and is configured to receive the interface, and a substantially centrally disposed extended portion including a plurality of air inlet passages; an O-ring configured to be circumferentially disposed proximate the interior surface of the end cap at the groove; a filter including a first end configured to be disposed adjacent the air inlet passages and the interior surface of the end cap and a second end; a retainer including a plurality of openings wherein the retainer is configured to be disposed proximate the second end of the filter so as to retain the filter proximate the air inlet passages and the openings; and means for fastening at least the housing and end cap.
 13. The compressor intake system of claim 10 wherein the fastening means is selected from the group consisting of press fit, adhesive, and at least one threaded bore disposed proximate an interior surface of the housing wherein each bore is configured to receive a threaded fastener disposed through an aperture in the end cap.
 14. The compressor intake system of claim 10 wherein the perimeter rim further includes a lip portion configured to extend beyond the interface and adjacent an exterior surface of the housing when the interface is received by the groove of the end cap.
 15. A compressor, comprising: an end cap including an interior surface, an exterior surface, a perimeter rim, and: a groove proximate the perimeter rim wherein the groove has a substantially similar circumference as, and is configured to receive, the interface; a substantially centrally disposed extended portion including a plurality of air inlet passages extending radially at 45 degree angle intervals with respect to the center of the extended portion; a plurality of spoke portions, each extending radially proximate the air inlet passages and extending from the extended portion toward the perimeter rim of the end cap; and at least one recessed portion disposed between at least two spoke portions; an O-ring configured to be circumferentially disposed proximate the interior surface of the end cap at the groove; a filter including a first end configured to be disposed adjacent the air inlet passages and the interior surface of the end cap and a second end; a retainer including a plurality of concentric openings disposed substantially radially with respect to the center of the retainer, wherein the retainer is configured to be disposed proximate the second end of the filter so as to retain the filter proximate the air inlet passages and the openings; and means for fastening at least the housing and end cap. 